Columnist Charly likes to keep system-critical daemons on two or more servers. If one of the servers fails, the idea is that the service can be started on the other and will be available at the same IP address – a scenario that works with or without the Pacemaker heartbeat.

Even hardened scientists can make mistakes when interpreting statistics. Mathematical experiments can give you the right ideas to prevent this from happening, and quick simulations in Perl nicely illustrate and support the learning process.

Organization charts, UML drawings, breadboard sketches, or plans for the new website – a drawing program is always the first port of call when you need to create a schematic diagram. We present four candidates for the Linux desktop.